Aluminized explosive composition



;ALUMINIZEDEXPLQSIYE 'QOMIOSITION Frank H. Westheimer, Chicago, 11].,and John W. Dawson, Philadelphia, Pa., assignors, by mesne assignments,to the United States of America as represented by the Secretary of theNavy No Drawing. Filed June 6, 1947, 'Ser. No. 753,058 8'Claims. (Cl.52-6) This invention relates to improvements in explosive. compositionsand more particularly to an aluminized explosive composition which has areduced tendency to spew or erupt during manufacture or storage.

It has been observed that aluminized compositions, f

example, those of the Minol type comprising ammonium nitrate,trinitrotoluene, and aluminum powder, have a tendency to evolve gasduring manufacture or storage. This is an undesirable property and isthought to be related to the amount of water present in or accumulatedby the aluminized composition during manufacture. In order to reducethis evolution of gas it has been proposed to dry the compositioncarefully. However, the drying process is difiicult and expensive. I

In accordance with one embodiment of this invention it has been foundthat aluminized explosive compositions having a reduced tendency to spewor form gas may be prepared by the addition of certain fatty acids' orfatty acid derivatives thereto. One compound that has been foundparticularly useful in this connection is stearoxyacetic acid. Only asmall amount of this material is necessary. Compounds of this characterin the explosive compositions of the Minol type, in addition todecreasing the tendency of the mixture to form gas, also increase thepourability of the composition, thus rendering it more easy to handleduring the loading of bombs and mines.

-. The desiccating compound and the fatty acid derivative in the finalmixture cooperate to reduce further the tendency of the composition togas.

Additionally, the fatty retreated June-28, rsao "Ice where RDX denotesthe compound cyclotrimethylenetrinitramine,

: acetic acid.

It will be apparent from the above that any desired concentrations ofthe magnesium compound or other desiccant and the fatty acid derivativemay be employed to obtain the desired results. However, the preferredrange of these materials is between about 0.2% to 4.0% by weightof themagnesium compound and between about .05 and .50% by weight of the fattyacid derivative, the relative proportions depending upon the amount ofwater originally present in the aluminized explosive composition.

We claim: v

1. A cast composition consisting essentially of about 18 parts by weightof powdered aluminum, about 0.5 part by weight of hydrophilic magnesiumnitrate, about 0.05 part by weight of stearoxyacetic acid, and about 82'parts by weight of an explosive containing approximately 40 parts oftrinitrotoluene, 21 parts of ammonium nitrate and 21 parts ofcyclotrimethylenetrinitramine.

2. A cast composition consisting essentially of about 18 parts by weightof powdered aluminum, about 0.5 part by weight of hydrophilic magnesiumnitrate, about 0.05 part by weight of stearoxyacetic acid, and about 82parts byweight of an explosive containing approximately 40 parts oftrinitrotoluene.

acid derivative serves to prevent any segregation of the mixture whichmay occur in the presence of the desiccant.

In accordance with one embodiment of this invention, an improved Minolcomposition may be prepared containing 3% by weight of magnesium nitratemonohydrate and about .15 of stearoxyacetic acid, the basic Minolcomposition comprising ammonium nitrate, TNT and aluminum powderin theweight ratio 2:2: 1 respectively.

' It was found that this mixture, although initially containing about.7% water, was as stable as a standard Minol composition whichhad beenpreviously subjected to a careful drying operation. By the addition ofthe magnesium compound and the stearoxyacetic acid, satisfactorilystabilized Minol may be obtained even though the amount of waterin the original Minol is initially as high as 1.2%. a

In accordance with another embodiment of the invention, a Torpex-typeexplosive having the following com- 3. A cast composition consistingessentially of about 18 parts by weight of powdered aluminum, about0.2-4.0% by weight of hydrophilic magnesium nitrate, about 0.05 to 0.50%by weight of a member selected from the group consisting ofstearoxyacetic acid, stearic acid, palmitic acid and oleic acid, andabout 82 parts by weight of an explosive containing approximately 40parts of trinitrotoluene.

4. A cast composition consisting essentially of about 18 parts by weightof powdered aluminum, about 0.2-4.0% by weight of hydrophilic magnesiumnitrate, about 0.05 to 0.50% by weight of stearoxyacetic acid, and about82 parts by weight of an explosive containing approximately 40 parts ,oftrinitrotoluene.

5. A cast composition consisting essentially of ammonium nitrate,trinitrotoluene and powdered aluminum in the weight ratio'2z2z 1,respectively, and containing about 02-40% by weight of magnesium nitrateand about 0.05-0.50% by weight of a member selected from the groupconsisting of stearoxyacetic acid, stearic acid, palmitic acid and oleicacid. 7

6. A cast composition consistingessentially of ammonium nitrate,trinitrotoluene and powdered aluminum in the weight ratio 2:2: 1,respectively, and containing about 0.24.0% by weight of magnesiumnitrate and about 0.05-0.50% by weight of stearoxyacetic acid.

7 A cast composition consisting essentially of ammonium nitrate,trinitrotoluene and powdered aluminum in the weight ratio 2:2: 1,respectively, and containing about 3% by weight of magnesium nitratemonohydrateand abaut 0.15% stearoxyacetic acid.

8. A cast composition consisting essentially of about 18 parts by weightof powdered aluminum, about 024.0%

by weight of a desiccant selected from the group consisting ofmagnesium'nitrate and calcium chloride, about 0.05-050% by weight of amember selected from the group consisting of stearoxyacetic acid,stearic acid, palmitic acid, and oleic acid, and about 82 parts byweight of an explosive containing approximately 40 parts' oftrinitrotoluene. v

References Cited in the file of this patent UNITED STATES PATENTS.4s7,0s0 Skoglund N09. 29, 1892 1,307,495 Hill et a1. June 24, 1919 4.Stoops Oct. 27; 1931 Crater Sept. 22, 1936 Bagley Feb. 13, 1945 FOREIGNPATENTS Great Britain"; 1893 Great Britain 1910 Great Britain 1913

3. A CAST COMPOSITION CONSISTING ESSENTIALLY OF ABOUT 18 PARTS BY WEIGHTOF POWDERED ALUMINUM, ABOUT 0.2-4.0% BY WEIGHT OF HYDROPHILIC MAGNESIUMNITRATE, ABOUT 0.05 TO 0.50% BY WEIGHT OF A MEMBER SELECTED FROM THEGROUP CONSISTING OF STEAROXYACETIC ACID, STEARIC ACID, PALMITIC ACID ANDOLEIC ACID, AND ABOUT 82 PARTS BY WEIGHT OF AN EXPLOSIVE CONTAININGAPPROXIMATELY 40 PARTS OF TRINITROTOLUENE.